Ignition device for a safety system

ABSTRACT

The invention relates to an ignition device ( 7 ) for a safety system, particularly an airbag, a belt tightener or similar in vehicles. According to the invention, means of ignition are arranged in a housing and can be activated by input signals which are fed via supply lines ( 3,4 ). At least one electronic component ( 10 ) is connected to the supply lines ( 3,4 ).

TECHNICAL DOMAIN

[0001] The invention relates to an ignition device for a safety system,especially an airbag, a belt tensioner, or the like in motor vehiclesaccording to the features of claim 1.

PRIOR ART

[0002] Austrian utility model AT 000522U1 discloses an ignition devicefor a safety system which can be a safety belt tensioner here. In thisignition device there are ignition means in the housing, the ignitionmeans receives signals for activation (i.e. for ignition) via feedlines.

[0003] To protect against voltages or currents which are formed byincident radiated electromagnetic fields or land-line HF waves, at leastone electronic component is connected to the feed lines, by which theincident radiated voltages or currents or HF waves are attenuated to theextent that they can no longer trigger misfires of the ignition means.

[0004] In this known ignition device it is necessary to place theelectronic component within the housing of the ignition device since itmay only occupy little installation space. For the case in which theelectronic component is faulty, it is necessary to replace the entireignition device.

DESCRIPTION OF THE INVENTION

[0005] The object of this invention is therefore to improve the knownignition device such that the indicated disadvantages are eliminated.

[0006] This object is achieved by the features of claim 1.

[0007] As claimed in the invention it is provided that at least oneelectronic component is located outside the housing of the ignitiondevice. In this way the electronic component can be located where thereis adequate space. In addition, the space requirement for at least oneelectronic component is thus no longer subject to limitations so that itin fact can be optimally configured with respect to its arrangement andits function while simultaneously maintaining its advantageous effects,specifically the effective prevention of misfires.

[0008] The electronic components can be coils (inductances), capacitors,varistors and the like. It also is conceivable for several of thesecomponents to be used in combination.

[0009] In a development of the invention the electronic component isconnected to the feed lines via at least partially electricallyconductive lines. This increases the flexibility of installation, sincefirst the feed lines are connected to carrier means and then theelectronic component is connected to the carrier means (or vice versa).Moreover different connecting techniques can be used in the connectionbetween a feed line and the carrier means on the one hand and thecarrier means and the component on the other. The optimum matching ofconnecting techniques ensures that both a durable connection can beestablished and also especially the electronic component is not damagedby the connection.

[0010] In one especially advantageous embodiment the carrier means aremade as stampings. By execution as stampings it is on the one handpossible to provide fixing means both for the electrically conductiveareas of the feed lines and also for the electronic component.Furthermore, by using a stamping the strength is increased and aninstallation site for the electronic component is formed. It isespecially important to increase strength, since feed lines are ingeneral flexible round conductors. Based on their flexibility, it isnecessary that at the site at which the component is inserted onto afeed line a minimum stiffness is attained. This minimum stiffness isfurther increased by the carrier means having a nonconducting carrier inthe manner as claimed in the invention. The stiffness also is increasedby a nonconductive carrier which consists, for example, of a plasticcomponent.

[0011] In a development of the invention at least the electroniccomponent is surrounded by a housing. In this way the electroniccomponent effectively is protected against ambient effects (especiallymechanical stress and moisture and electrically conductive particles).Of course, the carrier means and the feed lines directed to theelectronic components also can be surrounded by the housing. The housingitself can have either fasteners with which it is fixed at aninstallation site or can have a shape with which it can be fixed inposition.

[0012] In one development of the invention the housing, which surroundsthe electronic components, can be produced by an injection moldingprocess. After connecting the electronic component to electricallyconductive areas of the feed lines, especially using the carrier means,the prefabricated unit can be coated by an injection molding process (oroptionally by other likewise usable processes) in order to produce thehousing. An injection molding process works especially well since withit the housing can be quickly manufactured and reliably surrounds theparticipating components, especially also the ends of the feed lines, sothat mechanical strength is clearly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] One embodiment of the invention to which it is however notlimited is described below based on the steps of a production processand is explained in the figures.

[0014]FIG. 1 shows stampings,

[0015]FIG. 2 shows stampings with the carrier,

[0016]FIG. 3 shows stripped feed lines,

[0017]FIG. 4 shows stampings and the carrier which are inserted into thestripped areas,

[0018]FIG. 5 shows the installed electronic component,

[0019]FIG. 6 shows the electronic component surrounded with a housing.

IMPLEMENTATIONS OF THE INVENTION

[0020]FIG. 1 shows by way of example shaped stampings via which theelectronic component can be connected to electrically conductive areasof feed lines.

[0021]FIG. 2 shows that the stampings 1, which are both electricallyconductive, are fixed at a distance from one another using anelectrically nonconductive support 2. The support 2 can be a plasticpart into which the stampings 1 are inserted. But it also is conceivablefor the stampings 1 to be fixed in positions at a distance and for thecarrier 2 to be produced, for example, in an injection molding processsurrounding the stampings 1.

[0022] In FIG. 3 two feed lines 3, 4 are shown which are stripped sothat the conductors 5 and 6 are exposed. The stripped areas can belocated anywhere between a schematically shown ignition device 7 and alikewise schematically shown control unit 8 from which the signals foractivation of the ignition device originate. It should be mentioned herethat the electrical feed lines need not necessarily be made as roundflexible conductors. They also can be, for example, rigid flat striplines or flexible film lines.

[0023]FIG. 4 shows that the stripped areas are joined to the stampings 1and are, for example, soldered there. For fixing in position in front ofthe connection the stampings have bends 9, by which the conductors 5 and6 are held on the stampings 1. Instead of soldering it is conceivablehere for the conductors 5 and 6 to be crimped to the stampings 1 via thebends 9.

[0024]FIG. 5 shows the premounted unit now is provided with anelectronic component 10 which is electrically in contact with thestampings 1. Here it is shown that the electronic component 10 isconnected parallel to the two feed lines 3 and 4. Of course, theinvention also can be implemented when an electronic component isconnected within a feed line in series to this feed line. In addition,it is possible to connect one component (or several components) inparallel and another (or other components) in series to the feed lines.

[0025]FIG. 6 shows that the electronic component 10 including thestampings 1 and the carrier 2 are surrounded by a housing 11. Here thishousing 11 is shaped or is located around the premounted unit which isshown in FIG. 5 such that the ends of the feed lines 3 and 4 aresurrounded by the housing 11. Thus, a unit is formed which has requiredmechanical strength and which protects the sensitive electroniccomponent 10. The housing 11 can completely surround all participatingcomponents, it also can be conceivable, for example, for the carrier 2to project out of the housing 11 and to be used for attachment purposes.

[0026] In another alternative embodiment which is not shown, it isconceivable that the feed lines 3 and 4 point in the direction of theignition device 7 or also in the direction of the control unit 8, arenot made as feed lines, but as contact partners (especially pins orsleeves), these contact partners being surrounded in a structurallysuitable manner by the housing 11 in order to implement an electricalplug connection. Such an electrical plug connection has the advantagethat the electronic component 10 can be located outside the housing ofthe ignition device, but also in the vicinity in space. Alternatively itis possible for the electronic component 10 to be located within theelectrical plug connection on the control unit 8. In addition, the feedlines 3 and 4 which run from the electronic component on the one hand inthe direction of the ignition device 7 and on the other in the directionof the control unit 8 can be the same or also different.

1. Ignition device (7) for a safety system, especially an airbag, a belttensioner, or the like in motor vehicles, with ignition means which arelocated in the housing and which can be activated by signals suppliedvia feed lines (3, 4), at least one electronic component (10) beingconnected to the feed lines (3, 4), characterized in that the electroniccomponent (10) is located outside the housing of the ignition device(7).
 2. Ignition device (7) as claimed in claim 1, wherein theelectronic component (10) is connected to the feed lines (3, 4) via atleast partially electrically conductive carrier means.
 3. Ignitiondevice (7) as claimed in claim 2, wherein the carrier means are made asstampings (1).
 4. Ignition device (7) as claimed in claim 2 or 3,wherein the carrier means have an electrically nonconductive carrier(2).
 5. Ignition device (7) as claimed in one of the preceding claims,wherein at least the electronic component (10) is surrounded by ahousing (11).
 6. Ignition device (7) as claimed in claim 5, wherein thehousing (11) can be produced in an injection molding process.